Stuart Anderson wrote: > On Thu, Oct 18, 2007 at 12:00:52PM +1000, James C. McPherson wrote: >> Stuart Anderson wrote: >>> What is the current status of Sol10 support for mpxio and tape >>> drives (particularly FC 9940B drives)? It does not appear to be enabled >>> by default as is the case for FC disk devices. >> The most recent info that I have is that we don't >> enable MPxIO for tape drives, at all. >> >> >> Personally, even if I could enable MPxIO for a >> tape drive, I certainly would not do so given >> the nature of the medium. > > Probably a naive question, but what is the problem? If I have a > server with two paths to a tape drive and one path goes down why not > have the SCSI commands automatically use the remaining active path?
If you have one initiator which is happily grinding away reading and writing data on your tape, then another initiator comes along and wants to grab the device, you'll incur a bus reset and possibly even a scsi2/3 reservation takeover. The bus reset is the killer, though, since the standard behaviour for a tape drive on acceptance of a bus reset command is to halt all IO and rewind the currently-loaded tape to the start of the medium. I don't think you really want that to happen when you're in the middle of a backup! James C. McPherson -- Senior Kernel Software Engineer, Solaris Sun Microsystems _______________________________________________ storage-discuss mailing list [email protected] http://mail.opensolaris.org/mailman/listinfo/storage-discuss
